An examination of data covering the period 1976 to 2002 from New Zealand's Land Transport Safety Authority[1,2] a government agency, shows that New Zealand is replicating the experiences of Canada[3] and the US[4] where no effect of increased helmet use among cyclists can be detected from prevailing fatality trends. As with other studies, our analysis uses pedestrians as a control group since pedestrians are vulnerable road users and are likely to benefit equally with cyclists from general safety campaigns, such as those involving roadside breath-testing of motorists and speed surveillance using radar equipment.

Analysis

Figure 1 shows fatalities for New Zealand's cyclists and pedestrians. Because of the small cyclist numbers, fatalities have been aggregated into three year periods before and after January 1st, 1994 the date of NZ's helmet law.

Figure 1

Figure 2 shows pedestrian/cyclist fatality trend lines when scaled to 5.69:1 ratio. If there were a bicycle helmet effect the cyclist fatality line would decline faster than the pedestrian fatality line, but as can be seen there's no indication of such an effect, instead as can be seen, it is the pedestrian trend line which has turned downward.

Figure 2

Figure 3 shows cyclist fatalities in relation to pedestrians fatalities (as a percentages). This portrays much the same view as figure 2. If cyclist fatalities were declining at a faster rate than pedestrian fatalities as a result of uptake of helmets then the trend line would diverge downward around the date of the legislation's implementation. Instead it trends upward. From 1976 to the date of New Zealand's bicycle helmet legislation, cyclist fatalities in relation to pedestrian fatalities was 21% (387/1813). Post-legislation it rose to 24% (122/508).

Figure 3

Conclusions

As with Canada and the US, it does not appear that mass helmet use is contributing to the reduction in cyclist fatalities, at least not in any measurable way. For effective counter measures which reduce cycling fatalities see the analysis for Canada.
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